As shown in FIG. 11, thinning shears 50 have a comb blade 51 and a bar blade 52, and are a bladed hand tool for shearing what is caught between the two blades. The comb blade 51 has a number of slits at regular intervals. The thinning shears 50 shear hair that is caught between the tips of portions 53, which are called the teeth, formed by the slits, and the bar blade 52. At the same time, the thinning shears 50 do not shear hair inserted into the slits. As a result, the shears 50 can thin out the hair. As indicated with the base line 54, the bar blade 52 of the conventional thinning shears 50 is longer than the comb blade 51, or the bar blade 52 has the same length as that of the comb blade (which is not shown). Also, a tip 55 of the comb blade 51 and a tip 56 of the bar blade 52 each have a sharp corner of 90 degrees.
As shown in FIG. 12, when the thinning shears 50 are used for cutting hair 60, the thinning shears 50 are inserted across a bundle of the hair 60. In this situation, the thinning shears 50 are usually used under a condition in which the bar blade 52 is situated downward. The fact that almost all shears have the bar blade 52 longer than the comb blade 51 seems to be based on this reason. In this conventional haircutting method, the thinning shears 50 are not used under conditions where the tip of the thinning shears 50 contacts the skin of the scalp. Therefore, both the sharpness and length of the bar blade 52 are not factors to be taken into consideration.